Advice needed to help this rhodo thrive

Forwarded from 8Peonies

I have a rhododendron in a huge pot but it did not flower last year nor has it flowered this year yet.

Firstly, I do not know this type of rhododendron so am hoping that the photos I have attached will help you identify this specific type of rhododendron/plant.

Secondly, I would like to transfer this plant to the ground hoping that it will fare better than stuck in this pot; however, I am not sure of the health of the plant. Some leaves have been bored through by some insects, which I have trimmed some leaves but they seem to pursue this habit. How normal is this? However, as you will see by the condition of the stem, which is woody and dry, though its offshoots seem healthy, I am not sure if this plant is okay to transplant to continue into the ground.

Also, I plan to plant it next to a limelight hydrangea (panicle) but not sure if it would be okay to plant next to it if the rhododendron is badly infected with the same insects who bore the holes in the leaves of the rhodo or the bark of the stem. Would it affect the hydrangea? Any advice you may offer would be much appreciated. Thank you kindly.

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From these tiny pics it is not so clear, but I suspect Botryosphaeria or Phytophthora infection. Canker is serious disease on rhodos and can attack especially those plants, that are weak because of other conditions. Rhodos don't tolerate well heat, dry or alkaline soil, deep planting, frosts etc. In containers many of these underlying causes are often amplified.

 

As already noted - cannot see photos expanded

QUESTION - is this rhodo in your area Margot?

I have a coast friend this side of Salish Sea who insists on keeping a small rhodo in small container - poor thing!

Not sure how it’s still looking kind of ok

 

Hello!
Thank you all for your comments and advice.
Pauline

 

Hello @8Peonies. It is impossible to tell just by looking at the leaves which type of rhododendron you have - there are literally thousands of species and cultivars. Although yours seems reasonably well at the moment, there are several things to keep in mind before deciding whether to keep it or not. Some rhodos, like the dwarf varieties, can thrive in containers for some time but you can tell by the way yours has been drastically pruned back that it is a larger-growing sort. As @Georgia Strait has pointed out, the container it is in now is already too small.

Your mention of leaves bored through, possibly by insects, is concerning too and makes me wonder if root weevils may by hiding in the soil, ready to emerge soon and carry on notching the new leaves. That's different than 'boring through' however so, without photo evidence, I'm not sure. Root Weevils: Troublesome Rhododendron Pests
If you decide to plant it out in the garden, take a good look at the roots and remove any grubs you may find. You could even wash the roots. Growing Rhododendrons Successfully

When you talk about planting the rhodo next to the Limelight Hydrangea, you'd have to keep them 6 to 8 feet apart I think. The hydrangea itself can grow to 8-feet in diameter and who knows how wide the rhodo would spread. Both could be kept pruned to some degree but you have to allow for space between them. I don't think I'd worry too much about insects spreading from the rhodo to the hydrangea, especially at that distance apart.

All that being said, I would think twice about keeping the rhodo unless it has significant sentimental value to you. Not even knowing if it's a type you would admire and with concerns about its health, I'd buy a fresh new plant that will grow to the size you have available and be tolerant of the amount of sun your hydrangea requires since they'd be growing in the same conditions. A good website to see rhodos and learn about their requirements is: The American Rhododendron Society Welcomes You

 

Margot et al, thank you for your comments and advice. This has been most helpful in deciding how to proceed further. Thanks again! :)